Engine anatomy Quiz issue

Hi guys,

Just a little thing, but it's bugging me that it's there. I did the quiz for Engine Anatomy several weeks ago and noted it failed me for saying a Closed Deck is better for high performance engine builds. The answer was said to be Open Deck, which doesn't seem right at all to me. I went back to the video linked and it didn't really explain Open Deck vs Closed Deck from a performance perspective either.

If it is actually Open Deck is better, can someone please explain to me why? I doubt this is the case, but willing to be corrected if necessary. If not can this question please be corrected?

I would agree with you - perhaps one of the admin's will see this and comment?

There've been a couple of errors in the past, so might be one of those things.

Yeah just one of those things. Better to have it sorted for others learning too.

Forgot, my thinking, and I may be mistaken - there are two main reasons for cylinders to fail

a/ cracking or splitting down the bores due to cylinder pressure and/or major thrust side loading

b/ the unsupported top of the cylinder moving because of the major thrust loading

With an open deck there isn't the additional material at the top, that should give some additional strength, and prevent any flexing that may crack the bottom of the cylinder.

A closed deck should also stabilise the fire-ring that seals the head gasket, preventing any movement, or fretting, that may lead to failure. Depending on engine design, I would also expect the gasket seal to be better, as there should be less flexing of the block as the head is torqued.

Jared,

Thanks for posting! When something comes up in a quiz that doesn't make sense, it's either a mistake or there's good reason for the answer chosen. Either way it's a good learning opportunity.

I've taken a look at the engine anatomy quiz questions in the engine building course, as well as the other engine building course quizzes, and I'm not seeing the question you're referring to. Is it possible that was in a different course?

Hello Mike,

Ahh sorry. It was Engine Building Fundamentals course, not Engine Anatomy. My bad.

I was doing another quiz on this last night, and a couple of the answers also aren't right.

One regarding filing rigs says from the inside-out, where as Andre says outside-in. The other is about excessive bore clearance, apparently excessive blow-by is wrong despite André saying this.

If you could go through this one it would be appreciated 🙂